Automobile makers may soon require to disclose the emission levels with respect to each model of their vehicles. The government, keen on bringing more transparency on the emission front...

Automobile makers may soon require to disclose the emission levels with respect to each model of their vehicles. The government, keen on bringing more transparency on the emission front, is considering making such revelations mandatory, official sources told FE.

Currently, firms advertise on the salient features of their vehicles, including safety features and fuel efficiency, but are silent on how much the variants emit. Of course, they need to comply with the progressive Bharat Stage (BS) emission norms that differ based on the engine capacity, technology employed and the like.

The Automotive Research Association of India (ARAI), an industry-government venture under the ministry of heavy industries, tests all the models for emission levels and certifies them. While the Bharat Stage vehicular emission norms specify the limits prescribed for each pollutant from a vehicle, each engine, whether large or small in size, has its own emission pattern based on technology variations adopted by manufacturers.

So, industry experts point out, many larger engines could have lower particulate matter emission compared to smaller engines. However, the emissions levels can’t exceed the respective BS norms. The automobile industry too has repeatedly pointed out that the modern diesel technology, compared to petrol technology, results in close to 25% higher fuel efficiency which in turn results in about 20% lower CO2 emissions.

Under BS IV norms, in force in the national capital for passenger vehicles, carbon monoxide emission from petrol engines has a permissible limit twice that of diesel ones. On other parameters like hydro carbons and Nox, petrol engines are less polluting.